--- /dev/null
+This is gnushogi.info, produced by Makeinfo version 3.12h from
+gnushogi.texinfo.
+
+ This file describes how to use GNU shogi, a program which plays
+Shogi (Japanese chess).
+
+ Copyright (C) 1999 Michael C. Vanier and the Free Software
+Foundation, Inc.
+
+ Permission is granted to make and distribute verbatim copies of this
+manual provided the copyright notice and this permission notice are
+preserved on all copies.
+
+ Permission is granted to copy and distribute modified versions of
+this manual under the conditions for verbatim copying, provided that
+the entire resulting derived work is distributed under the terms of a
+permission notice identical to this one.
+
+ Permission is granted to copy and distribute translations of this
+manual into another language, under the above conditions for modified
+versions, except that this permission notice may be stated in a
+translation approved by the Free Software Foundation.
+
+\1f
+File: gnushogi.info, Node: Top, Next: (dir), Prev: (dir), Up: (dir)
+
+GNU Shogi (Japanese chess)
+**************************
+
+* Menu:
+
+* Introduction:: What is GNU shogi?
+* License:: The GNU General Public License.
+* About shogi:: General information, rules, etc.
+* gnushogi:: How to play GNU shogi (gnushogi).
+* xshogi:: The X interface to GNU shogi.
+* References and links:: Where to go for more information.
+* Acknowledgements::
+* Bugs:: Where and how to report bugs.
+* Index::
+
+\1f
+File: gnushogi.info, Node: Introduction, Next: License, Prev: Top, Up: Top
+
+Introduction
+************
+
+ GNU shogi is a program that plays shogi, the Japanese version of
+chess, against a human (or computer) opponent. This file describes how
+to use GNU shogi and also gives background information about the game
+of shogi.
+
+ This file describes GNU shogi version 1.3. It was written by me,
+Mike Vanier, the current maintainer of GNU shogi. My email address is
+<mvanier@bbb.caltech.edu>.
+
+ GNU shogi is actually two programs:
+
+
+`gnushogi'
+ is the text-based program which also contains the game-playing
+ engine.
+
+`xshogi'
+ is the X-windows graphical interface to gnushogi.
+
+
+ Since xshogi invokes gnushogi, most players will just type "xshogi"
+and start playing.
+
+ Disclaimer: I use the personal pronouns "him", "his" etc. to refer
+to a shogi player regardless of gender. That's easier than writing
+"his or her" all over the place. I don't mean to infer that women
+don't play shogi; in fact shogi is very popular in Japan among women as
+well as men.
+
+\1f
+File: gnushogi.info, Node: License, Next: About shogi, Prev: Introduction, Up: Top
+
+GNU GENERAL PUBLIC LICENSE
+**************************
+
+ Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.
+ 675 Mass Ave, Cambridge, MA 02139, USA
+
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+Preamble
+========
+
+ The licenses for most software are designed to take away your
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+
+How to Apply These Terms to Your New Programs
+=============================================
+
+ If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these
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+
+ To do so, attach the following notices to the program. It is safest
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+ Copyright (C) 19YY NAME OF AUTHOR
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+ Gnomovision version 69, Copyright (C) 19YY NAME OF AUTHOR
+ Gnomovision comes with ABSOLUTELY NO WARRANTY; for details
+ type `show w'.
+ This is free software, and you are welcome to redistribute it
+ under certain conditions; type `show c' for details.
+
+ The hypothetical commands `show w' and `show c' should show the
+appropriate parts of the General Public License. Of course, the
+commands you use may be called something other than `show w' and `show
+c'; they could even be mouse-clicks or menu items--whatever suits your
+program.
+
+ You should also get your employer (if you work as a programmer) or
+your school, if any, to sign a "copyright disclaimer" for the program,
+if necessary. Here is a sample; alter the names:
+
+ Yoyodyne, Inc., hereby disclaims all copyright interest in the program
+ `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+ SIGNATURE OF TY COON, 1 April 1989
+ Ty Coon, President of Vice
+
+ This General Public License does not permit incorporating your
+program into proprietary programs. If your program is a subroutine
+library, you may consider it more useful to permit linking proprietary
+applications with the library. If this is what you want to do, use the
+GNU Library General Public License instead of this License.
+
+\1f
+File: gnushogi.info, Node: About shogi, Next: gnushogi, Prev: License, Up: Top
+
+About the game of shogi
+***********************
+
+ "Japanese chess cedes nothing in depth or beauty to the European
+ game... it is at least as interesting."
+
+ -- Alexander Alekhine
+ (quoted in David Pritchard, `The Encyclopedia of Chess Variants')
+
+
+ "... shogi [is] by far the most complex form of chess that has ever
+ achieved widespread popularity."
+
+ -- R. Wayne Schmittberger, `New Rules for Classic Games'
+
+
+ Shogi is the version of chess played in Japan. It is strikingly
+different from standard chess (which I shall refer to henceforth as
+"international chess") and also to all other regional variants, because
+captured pieces can re-enter play on the side of the capturer. This
+has several interesting effects on the play of the game:
+
+
+ 1. Shogi is much more complex than international chess, at least in
+ terms of the average number of possible moves per turn (estimated
+ at about 35 for chess and at about 80 for shogi).
+
+ 2. There are almost no draws (about 1-2% of all games in professional
+ play).
+
+ 3. Exchanges complicate the play rather than simplifying it.
+
+ 4. There are no "endgames" in the standard chess sense; all pieces
+ remain in play throughout the game. Games typically end in a race
+ to checkmate the other player before being checkmated oneself.
+
+ 5. Ownership of a piece is not indicated by the color of the piece;
+ instead, pieces are wedge-shaped and point towards the opponent.
+ The name of the piece is inscribed in Kanji characters on the
+ front of the piece.
+
+ 6. Most importantly: it's more fun than other forms of chess :-)
+
+
+
+ Shogi is extremely popular in Japan; it has been estimated that 20
+million Japanese can play shogi, of which perhaps 1 million are active
+players. It is even more popular there than the game of go, Japan's
+other favorite board game. There are a number of professional players
+who make a considerable amount of money playing in shogi tournaments,
+and the game receives extensive newpaper and television coverage.
+Despite this, the game has yet to become popular outside of Japan. Part
+of this is because the Kanji characters on the pieces scare away some
+people, but mostly it's due, I think, to lack of exposure to the game
+and to the difficulty of finding opponents. I hope that GNU shogi will
+help introduce shogi to a wider audience.
+
+* Menu:
+
+* The rules of shogi::
+* Sample game::
+* Mating problems::
+* Shogi variants::
+* Differences between shogi and chess::
+
+\1f
+File: gnushogi.info, Node: The rules of shogi, Next: Sample game, Prev: About shogi, Up: About shogi
+
+The rules of shogi
+==================
+
+ Shogi is a two-person abstract strategy board game with full
+information (i.e. all pieces and moves are visible to both players at
+all times). It is in the chess family, being descended from the same
+ancestral game as international chess: the Indian game of Chaturanga.
+The two players are referred to as "Black" and "White", with Black
+moving first (unlike in international chess, where White moves first),
+and with movement alternating between the two players. Note that
+"Black" and "White" are just names; the pieces are not colored.
+Instead, they are flat, wedge-shaped pieces which point towards the
+opponent. The identity of a given piece is indicated by two Japanese
+Kanji characters on each piece. In fact, only the top character is
+needed to identify the piece and thus only the top character is used in
+shogi diagrams. I will use alphabetical equivalents in the diagrams
+here; to see what the Kanji characters look like, start up xshogi
+(*note xshogi::.) and compare the starting setup there with the
+starting setup in this file (*note The opening setup::.).
+
+ The object of the game is to capture the opponent's King. The board
+is a grid of 9x9 uncolored squares, and pieces are placed on the
+squares. Each player begins with 20 pieces, described in the next
+section. Capture is by displacement, as in international chess.
+
+* Menu:
+
+* The moves of the pieces::
+* The opening setup::
+* Promotion of pieces::
+* Drops::
+* Winning the game::
+* Draws::
+* Handicaps::
+* Notes for chess players::
+
+\1f
+File: gnushogi.info, Node: The moves of the pieces, Next: The opening setup, Prev: The rules of shogi, Up: The rules of shogi
+
+The moves of the pieces
+-----------------------
+
+ Each player at the beginning of a shogi game has a total of 20
+pieces of eight different types. The moves of the shogi pieces can be
+divided into three classes: "stepping" pieces, that only move one
+square at a time; "ranging" pieces that move any number of unobstructed
+squares in a line, and "jumping" pieces that can jump over obstructing
+pieces to reach their destination squares. Most pieces can also
+promote to different (usually stronger) pieces under certain
+circumstances (see the next section). All pieces capture the same way
+that they move (even pawns). The piece moves and promotions are as
+follows; each piece name is followed by the standard piece abbreviation:
+
+ 1. The king (K). The king can move one square in any horizontal,
+ vertical, or diagonal direction, just like the king in
+ international chess. The king does not promote.
+
+ 2. The rook (R). The rook can move any number of squares in a
+ horizontal or vertical direction. The rook is the same as the
+ rook in international chess (except that it can promote). A rook
+ promotes to a "dragon king" or "dragon" for short (often just
+ referred to as a "promoted rook"), which can move as a rook or can
+ move one square in any diagonal direction.
+
+ 3. The bishop (B). The bishop can move any number of squares in a
+ diagonal direction. The bishop is the same as the bishop in
+ international chess (except that it can promote). A bishop
+ promotes to a "dragon horse" or "horse" for short (often just
+ referred to as a "promoted bishop"), which can move as a bishop or
+ can move one square in any horizontal or vertical direction.
+ Note: the horse should not be confused with a knight (see below),
+ as they are two completely different pieces.
+
+ 4. The gold general (G). A gold general can move one square in any
+ horizontal or vertical direction, or one square in a forward
+ diagonal direction. Gold generals do not promote.
+
+ 5. The silver general (S). A silver general can move one square in
+ any diagonal direction, or one square straight forward. A silver
+ general promotes to a gold general.
+
+ 6. The knight (N). A knight can move one square straight forward
+ followed by one square to either forward diagonal, jumping over
+ intervening pieces if any. In other words, a knight moves like
+ its international chess counterpart, but forward only. A knight
+ promotes to a gold general. The knight is the only jumping piece,
+ as in chess.
+
+ 7. The lance (L). A lance can move any number of squares straight
+ forward. A lance promotes to a gold general.
+
+ 8. The pawn (P). A pawn can move one square straight forward. The
+ pawn captures the same way that it moves, in contrast to
+ international chess. There is also no initial two-space move for
+ pawns and no _en-passant_ capture. A pawn promotes to a gold
+ general; a promoted pawn is usually known as a "Tokin".
+
+
+\1f
+File: gnushogi.info, Node: The opening setup, Next: Promotion of pieces, Prev: The moves of the pieces, Up: The rules of shogi
+
+The opening setup
+-----------------
+
+ The opening setup for shogi is as follows:
+
+ 9 8 7 6 5 4 3 2 1
++--------------------------------------------+
+| wL | wN | wS | wG | wK | wG | wS | wN | wL | a
++--------------------------------------------+
+| | wR | | | | | | wB | | b
++--------------------------------------------+
+| wP | wP | wP | wP | wP | wP | wP | wP | wP | c
++--------------------------------------------+
+| | | | | | | | | | d
++--------------------------------------------+
+| | | | | | | | | | e
++--------------------------------------------+
+| | | | | | | | | | f
++--------------------------------------------+
+| bP | bP | bP | bP | bP | bP | bP | bP | bP | g
++--------------------------------------------+
+| | bB | | | | | | bR | | h
++--------------------------------------------+
+| bL | bN | bS | bG | bK | bG | bS | bN | bL | i
++--------------------------------------------+
+
+
+ Here, "b" stands for "black" and "w" stands for "white", so that,
+for instance, "bL" means "black lance". The numbers above the files
+and the letters to the right of the ranks represent the most common
+notation system used for shogi by westerners (the Japanese also use
+Arabic numerals for the files but use Japanese numerals for the ranks).
+
+\1f
+File: gnushogi.info, Node: Promotion of pieces, Next: Drops, Prev: The opening setup, Up: The rules of shogi
+
+Promotion of pieces
+-------------------
+
+ In sharp contrast to international chess, where only pawns can
+promote to higher-ranked pieces, most of the pieces in shogi can
+promote. The promoted ranks are discussed in the section on piece
+moves (*note The moves of the pieces::.) but are repeated here for
+reference:
+
+Pawn
+ promotes to gold general (called a `tokin' in this case only).
+
+Lance
+ promotes to gold general.
+
+Knight
+ promotes to gold general.
+
+Silver general
+ promotes to gold general.
+
+Gold general
+ does not promote.
+
+Bishop
+ promotes to "dragon horse" or just "horse" for short. The horse
+ can move as a bishop or can move one square in any orthogonal
+ direction.
+
+Rook
+ promotes to "dragon king" or just "dragon" for short. The dragon
+ can move as a rook or can move one square in any diagonal
+ direction.
+
+King
+ does not promote.
+
+
+ The three ranks furthest away from each player constitute his/her
+"promotion zone". A player may, but is not required to, promote a
+piece after making a move in which the piece begins and/or ends in the
+promotion zone. Thus you can promote a piece when moving the piece into
+the promotion zone, out of the promotion zone, or entirely within the
+promotion zone. Promotion is mandatory in these cases:
+
+
+ 1. You must promote a pawn or a lance after moving it to the last
+ rank.
+
+ 2. You must promote a knight after moving it to either of the last
+ two ranks.
+
+
+
+ These forced promotions ensure that a piece cannot be moved to a
+square from which it would have no further move.
+
+ Pieces "dropped" onto the board (*note Drops::.) always drop in the
+unpromoted state, even if they drop into the promotion zone.
+
+\1f
+File: gnushogi.info, Node: Drops, Next: Winning the game, Prev: Promotion of pieces, Up: The rules of shogi
+
+Drops
+-----
+
+ When a player captures a piece, that piece is not removed from play.
+Instead, it becomes the property of the capturer and can re-enter play
+by being placed on (almost) any vacant square during the player's move.
+This is known as a "drop" and counts as a full move (in other words,
+you can either move a piece on the board or drop a piece onto the board
+during your move, but not both). All pieces drop in the unpromoted
+state. Pieces may be legally dropped in their promotion zone, but they
+do not promote on that turn.
+
+ There are several restrictions on drops:
+
+ 1. A pawn may not be dropped onto a file if there is already an
+ unpromoted pawn belonging to the same player on that file. It is
+ legal to drop a pawn on a file which contains a _promoted_ pawn
+ belonging to the same player, however.
+
+ 2. A pawn may not be dropped to give immediate checkmate on the move.
+ A pawn is, however, permitted to be moved on the board to give
+ immediate checkmate. This is a curious rule, and if anyone knows
+ the reason for it I would appreciate it if they would contact me
+ and explain it to me :-)
+
+ 3. A pawn or piece may not be dropped onto a square from which they
+ would have no legal move. This means that pawns and lances may
+ not be dropped onto the last rank, and the knight may not be
+ dropped onto the last or second-to-last rank.
+
+
+ It is entirely permissible (and often advisable) to drop a piece or
+pawn between one's King and an attacking ranging piece. For this
+reason, the final checkmating move is nearly always an attack on the
+King from an adjacent square (except for an attack by a Knight).
+
+ Captured pieces are said to be pieces "in hand".
+
+ The drop is the primary distinguishing feature of Japanese chess,
+shared with no other popular chess-type game. It gives shogi a very
+aggressive quality, and dramatically increases the number of possible
+moves once a few pieces have been captured. Another interesting
+feature of shogi is that exchanges complicate play rather than
+simplifying it (as in international chess), because of the drop rule.
+
+\1f
+File: gnushogi.info, Node: Winning the game, Next: Draws, Prev: Drops, Up: The rules of shogi
+
+Winning the game
+----------------
+
+ A game of shogi is won by capturing the opponent's king. In general,
+this is done by checkmating the king: attacking the king in such a way
+that the king cannot be defended no matter what the defending player
+moves. Note, though, that there is no rule that requires a player to
+defend a king which is being attacked. However, if he does not defend
+his king, the opponent is entirely free to capture it on the next move,
+thus winning the game. As in international chess, in practice most
+games end by resignation when one player realizes that he cannot escape
+checkmate.
+
+\1f
+File: gnushogi.info, Node: Draws, Next: Handicaps, Prev: Winning the game, Up: The rules of shogi
+
+Draws
+-----
+
+ There are very few draws in shogi; only about 1-2% of professional
+games end in a draw. One reason for this is that material can never be
+depleted as in chess, because captured pieces are constantly re-entering
+play as a consequence of the drop rule. In fact, most of the ways a
+game can be drawn in chess are not allowed in shogi:
+
+
+ * Draws cannot be offered.
+
+ * There is no fifty-move rule.
+
+ * A stalemate counts as a win for the stalemater. Stated otherwise:
+ if you can't move, you lose.
+
+ * Perpetual check is illegal (see below).
+
+
+
+ There are only two legal ways in which a draw can occur:
+
+
+ 1. A position (including the pieces in hand) occurs 4 times with the
+ same player to move (called "Sennichite"). However, if this is
+ caused by consecutive checks (direct attacks on the King,
+ threatening to capture it on the next move) by one side, the
+ player giving these checks loses the game. In other words,
+ perpetual check results in a loss for the attacker who recreates
+ the same position the 4th time.
+
+ 2. Both players have moved their King into the the promotion zone (or
+ they cannot be prevented from doing so) and the Kings cannot be
+ checkmated. A King who has entered the promotion zone is known as
+ an "entering King"; due to the forward orientation of most shogi
+ pieces, it is very hard to mate such a King. In that case the
+ players may decide to count their pieces as follows: the King does
+ not count, the Rook and Bishop count as 5 points, and all other
+ pieces as one point. Promotion is disregarded. If both players
+ have at least 24 points the game is a draw (called "Jishogi"). If
+ a player has less, he loses the game.
+
+ Of course, a player can refuse to count pieces when he still has
+ mating chances or chances to gain material which would affect the
+ outcome of the counting. There is no strict rule about what to do
+ if this is not the case, but nonetheless a player refuses to count
+ up (e.g. because he does not have enough points for a draw). It
+ has been generally accepted that in such a case the game ends and
+ the pieces are counted after one player has managed to get all his
+ pieces protected in the promotion zone.
+
+
+
+\1f
+File: gnushogi.info, Node: Handicaps, Next: Notes for chess players, Prev: Draws, Up: The rules of shogi
+
+Handicaps
+---------
+
+ Unlike international chess, shogi has a well-established handicap
+system which is used when players of different strengths play against
+each other. Handicaps range from small to huge, which makes it
+possible for weak players to play against even very strong players and
+have an even chance of winning.
+
+ Shogi players are ranked as follows: the weakest rank is around 15
+"kyu", which represents a beginner. 14 kyu is higher than 15 kyu, 13
+kyu is higher still, and so on until you get to 1 kyu. The next highest
+rank is 1 "dan", followed by 2 dan, 3 dan and so forth. The highest
+amateur rank is 6 dan; professionals go up to 9 dan. However,
+professional ranks are not the same as amateur ranks; a professional 1
+dan is _much_ stronger than an amateur 1 dan. This system is similar
+to that used by go players (and also other Japanese sports such as
+karate).
+
+ A handicap consists of the stronger player playing White and removing
+one or more pieces from his side of the board at the start of the game.
+These pieces are permanently removed from play; they are not in hand.
+
+ The following is a list of the accepted handicaps, from weakest to
+strongest. The degree of the handicap, represented by the position in
+the list, represents the difference in rank between the two players for
+which the handicap is appropriate. These rules are taken from the books
+"Shogi for Beginners" by John Fairbairn and "The Art of Shogi" by Tony
+Hoskings (*note References and links::.) and, I believe, represent
+current Japanese practice.
+
+
+ 1. The stronger player removes his left lance (on 1a).
+
+ 2. The players play a two-game match; in the first game the stronger
+ player removes his left lance (on 1a), while in the second game he
+ removes his bishop.
+
+ 3. The stronger player removes his bishop.
+
+ 4. The stronger player removes his rook.
+
+ 5. The stronger player removes his rook and left lance.
+
+ 6. The players play a two-game match; in the first game the stronger
+ player removes his rook and left lance (on 1a), while in the
+ second game he removes his rook and bishop.
+
+ 7. The stronger player removes his rook and bishop. This is usually
+ called a "two-piece" handicap.
+
+ 8. The stronger player removes his rook, bishop, and both lances.
+ This is called a "four-piece" handicap.
+
+ 9. The stronger player removes his rook, bishop, both lances, and both
+ knights. This is called a "six-piece" handicap.
+
+ 10. The stronger player removes his rook, bishop, both lances, both
+ knights, and both silvers. This is called an "eight-piece"
+ handicap.
+
+
+
+ Another advantage of playing handicap games is that the handicaps
+alter the optimal strategy for both players. For instance, handicaps
+all have their own opening lines which may bear little or no
+resemblance to those used in non-handicap shogi. This means that when
+learning handicap shogi, you are essentially learning completely new
+games which use the same equipment!
+
+ The reader may wonder how on earth a player giving an eight-piece
+handicap, say, could possibly hope to win. Don't forget, though, that
+in shogi the opponent's pieces can be captured and then become part of
+one's own army. Thus, if the opponent plays badly enough, the number of
+pieces will soon even out.
+
+\1f
+File: gnushogi.info, Node: Notes for chess players, Prev: Handicaps, Up: The rules of shogi
+
+Notes for chess players
+-----------------------
+
+ Here are a few miscellaneous things that may confuse chess players.
+Some of these have been mentioned elsewhere, but they bear repeating.
+
+
+ 1. There is no queen.
+
+ 2. Pawns capture the same way they move. There is no initial
+ two-space pawn move and no _en-passant_ move.
+
+ 3. There is no special castling move. There _are_ a large number of
+ possible defensive formations referred to as "castles" (*note
+ Sample game::.) but there is no need for special moves to create
+ them.
+
+ 4. A given piece can only promote to _one_ other kind of piece.
+
+
+
+\1f
+File: gnushogi.info, Node: Sample game, Next: Mating problems, Prev: The rules of shogi, Up: About shogi
+
+Sample game
+===========
+
+ This game was annotated by Pieter Stouten (*note References and
+links::.). I have made some minor corrections. Note that captures are
+denoted by the "x" symbol e.g. Rx3f and drops are denoted by the "*"
+symbol e.g. R*3f. Check is indicated by a "+" after the move, e.g.
+R3f+. I recommend you use gnushogi/xshogi to play along with this
+game. In xshogi simply hit the "Force Moves" button after starting up,
+while in gnushogi enter the word "force" at the prompt. This will
+allow you to enter moves for both sides.
+
+ Note also that the move numbering system used here is the chess-type
+system where one move means one move by each player. The Japanese count
+one move made by each player as two moves.
+
+--------------------------------------------------------------------------
+
+ Below you will find (the English translation of) an annotated game
+which was published in the Dutch Shogi magazine "81" and in the Dutch
+beginners booklet. It has proven to be a very useful game to explain
+some basic principles of Shogi. Also, it is a rather straightforward
+game compared to professional games where in most cases very diffuse
+middle game fights take place.
+
+ Pieter Stouten, 14th May 1990.
+
+--------------------------------------------------------------------------
+
+ Black: Michael Trent (1-dan). White: David Murphy (2-dan).
+
+ 1. P2f P3d 2. P2e B3c
+[ This move is necessary, as otherwise white can exchange pawns: 3. P2d
+Px2d 4. Rx2d. He would thus get a pawn in hand and open up his rook
+file. ]
+
+ 3. P7f P4d
+[ White closes the bishop diagonal again. He plans to play ranging rook
+(the rook goes to 5b, 4b, 3 or 2b; a defensive strategy) and in that
+case he'd better avoid an exchange of bishops. One of the reasons is
+that he will have problems developing his pieces without leaving holes
+for bishop drops. ]
+
+ 4. S4h R3b 5. P3f S4b 6. K6h K6b
+[ In general the rook plays an important role in the attacks. It is
+wise to move the king away from the area where the initial fights will
+be and both players act according to the Shogi proverb "keep the rook
+and king apart". ]
+
+ 7. K7h K7b 8. P5f P5d 9. G4i-5h G4a-5b
+[ Both players use their second gold general to build their castle. ]
+
+ 10. S6h
+[ In itself this move is not bad. However, it will become clear that
+black plans a quick attack and in that case it is wiser to omit this
+move. ]
+
+ 10... S5c 11. P1f P1d
+[ The advance of the edge pawns must be timed very well. The remark at
+black's tenth move applies here too: this move is good if black wants to
+play a slow game, because it eliminates a future B1e. ]
+
+ 12. P4f K8b 13. N3g S7b
+[ Black develops his knight in order to start an attack over the second,
+third and fourth files. White strengthens his king's position and
+awaits the attack. He aims at a counterattack as soon as black has
+broken through into the white camp. Probably white's breakthrough will
+take place later, but he has good compensation in the form of a stronger
+castle. This theme occurs very often in static rook versus ranging rook
+games. ]
+
+ 14. P4e R4b
+[ Black starts his attack and white puts up a very passive defence. His
+rook has a hard task now to penetrate the black position. Moreover, he
+blocks his own bishop. It seems much better to start a counterattack
+with 14... P3e, later to be followed by B2b, B5a or Bx4d in order to use
+his rook more actively. ]
+
+ 15. Px4d Sx4d 16. P*4e S5c
+[ 16... Sx4e is more active. A silver general is normally more valuable
+than a knight, but white gets two pawns in hand and black none, while
+the knight might come in handy for white too. ]
+
+ 17. Bx3c+ Nx3c 18. P2d Px2d
+[ Black threatens to break through and white has to consider taking the
+pawn on 2d or starting a counterattack with Nx4e. If he chooses the
+latter, black can play Px2c+ followed by +P3c. The disadvantage is the
+black "tokin" (=promoted pawn) that white will get in his camp; the
+advantage is that it will cost black two more moves to promote his rook.
+Because white did not trust that the result after engaging in a
+"semeai" (=mutual attack) with 18...Nx4e would give a positive result,
+he captured the pawn on 2d. Making the right decision in moments like
+this often makes the difference between a win and a loss: miss one
+attacking chance and you will be forced to defend the whole game until
+the unavoidable defeat; on the other hand, an unsound attack can destroy
+all "aji" (=potential, meaning possibilities, threats) without getting
+anything in return. ]
+
+ 19. Rx2d Nx4e 20. Nx4e Rx4e 21. R2a+ P*4g
+[ Now it becomes clear why black's 10. S6h was not good. Had this move
+been omitted, then white would not have had the time to play 13... S7b
+and after R2a+ the gold on 6a would hang. Thus black would have kept
+"sente" (=initiative). Instead of 21... P*4g, B*6d is a very good
+move, because after 22. P*2h black does not have a pawn in hand anymore
+and he is being threatened with the annoying 22... N*4f 23. G5g N3h+
+24. S4g +N4h also. Black can also counter 21... B*6d with 22. N*3g.
+White would then reply with 22... R4b 23. B*3c P*4g 24. Bx4b+ Sx4b. The
+white rook has played its role and instead of spending moves on saving
+it white starts to scatter black's defences by successive pawn drops on
+the fourth file: 25. Gx4g P*4f 26. G5g N*6e 27. G5h P4g+ 28. Gx4g P*4f.
+This analysis was provided by Kato Hifumi, 9-dan professional (the
+highest regular grade). Destroying the coherence of the enemy pieces
+(their shape) by dropping pawns is one of the most important Shogi
+techniques. With the actual move 21... P*4g white missed a good
+chance. ]
+
+ 22. Sx4g P*4f 23. B*3g Px4g+ 24. +Rx6a +Px3g
+[ 23. B*3g seems pointless, but a closer look reveals that it is
+actually quite mean. On move 24 white cannot capture black's "Ryu"
+(=dragon =promoted rook) with his silver: 24... Sx6a 25. N*7d K7b 26.
+G*8b mate. By attacking the front of the white castle and threatening
+to mate him there, black has the chance to break down the white
+defences from the side. ]
+
+ 25. +Rx5b S*6b
+[ Here 25... B*4d would be much better, because it is defensive and
+attacking at the same time. After e.g. 26. G*4c Bx9i+ 27. Gx5c black
+threatens 28. +Rx7b Kx7b 29. S*6a K8b 30. S*7a Kx7a 31. G*7b mate.
+White is one move quicker, however. He has the following beautiful
+"tsume" (mating sequence where every move is check): 27... N*8f 28. Px8f
+S*8g 29. Kx8g B*9h 30. K7h Bx8i+ 31. K8g +B8i-8h 32. K9f L*9e mate.
+This illustrates the sharpness of Shogi: one move can make the
+difference between winning and losing. ]
+
+ 26. P*4f Rx4f
+[ This move eliminates white's last chances. 26... R4b 27. +Rx4b Sx4b
+28. R*4a seems annoying, but after 28... B*3c 29. S7g B*3b white wins
+the rook and with his "tokin" on 3g there still is some hope. ]
+
+ 27. N*6e +P4g
+[ White cannot defend anymore, so he starts a desperate attack. Black
+does not lose the right track, however. ]
+
+ 28. Nx5c+ +Px5h 29. +Nx6b +Px6h 30. Gx6h N*8f 31. Px8f B*6i 32.
+Gx6i R4h+ 33. N*6h +Rx6h 34. Gx6h S*8g 35. Kx8g N*9e 36. K7h
+Resigns
+[ White resigns here, because after 36... B*8g 27. K7g his attack has
+petered out. ]
+
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